The
extensive observations of this supernova confirm it occurred 167,000 years ago

Geno Castagnoli

There are several links at the
bottom of this page that I urge everyone to visit and bookmark, if for no other reason than
they have a lot of really great images.

Introduction

One of the main tenets
of creation 'science' (at least the 'young earth creationist' or YEC version
of it)
is that the earth and universe are only 6000 years old. It is my purpose, in
this work, to show that SN1987A is about 167,000 light years away and that
the event at SN1987A occurred about 170,000 years ago. This refutes the YEC
claim that the universe is only 6000 years old. In doing so, it also falsifies
YEC as a scientific explanation for the origins of the Universe.

The
findings of physics, astronomy and so on have long
demonstrated that the universe is billions of years old, as evidenced by our ability to
see stars that are billions of light years away. Creationist criticisms
of this view usually
fall into one of three categories:

God created the universe with the
light from apparently distant stars 'intact' and in transit and so we can see them now (this is a totally unscientific
explanation as it requires a supernatural act or miracle - consequently I will
not address this point further in this work)

The speed of
light is decreasing and hence light could have traveled much greater distances
in the past (this is counter to scientific observations)

The
observations of science regarding the distance of stars and galaxies are subject
to error because they rely on 'indirect' measurements
(such as measurements of redshift, brightness, and so on). This also runs
counter to current science, but until
the observations of SN1987A were made this was, at least, a debatable
point.

SN
1987A light pulse propagation

However,
an event was observed on February 23,
1987, that allows us to lay to rest the second and third creation 'science' arguments above.
This event was the observation of Star 1 of the Sanduleak - 69 202 trio in the
Tarantula Nebula, part of the Large Magellanic Cloud, going supernova and earning a
new name: SN1987A (1). It was the most luminous supernova recorded
since Kepler's star of 1604 and the first since then to have been observed in
the Milky Way complex. In going supernova, it became one of the most studied
astronomical objects of the last 15 years. There are more than 1700
astronomical papers that mention '1987A' in their title.

As a result of
that event, we were able to make a direct trigonometric measurement of the
distance to that supernova of nearly 167,000 light years. This is now the most
distant object ever measured by direct triangulation. Also, other measurements
have been made that confirm the speed of light has not changed appreciably since
it left SN1987A.

The original paper in which Panagia et al measured the
distance to SN1987A (2) is available online here.

From the abstract of the Panagia
et al paper:

We have
determined the distance to the SN 1987A by comparing the angular size of its
circumstellar ring measured from an HST (Hubble Space Telescope) image
... with its absolute size derived from an analysis of the light curves of narrow
UV lines ... measured with IUE (International
Ultraviolet Explorer). Our analysis confirms that the observed elliptical
structure is indeed a circular ring at an inclination of 42.8° ± 2.6°.
and provides a determination of its absolute diameter (1.27 ± 0.07) x 1018
cm. Its ratio to the angular diameter of 1.66" ± 0.03" ... gives an
accurate
determination of the distance to SN 1987A ... = 51.2 ± 3.1 kpc.... This value
agrees very well with the determinations obtained from light-curve analysis of
variable stars

An image of the circumstellar ring analyzed
by Panagia et al

Thus, Panagia et
al established the
distance to SN1987A at 166,912 +/- 10.1 light years as one parsec is 3.26 light years,
and one kiloparsec (kpc) is 3260 light years. This measurement is in good
agreement with previous estimates of the distance to the Large Magellanic
Cloud of 143,000 to 179,000 light years. In making this measurement, Panagia
et al have
effectively refuted creationist claims that distances much greater than 100 light
years
have not been measured accurately.

SN1987A
shock wave propagation

The Panagia et al findings were confirmed
when the long anticipated shock wave from the supernova explosion reached the
ring. Predictions of the shock wave (3) (4) were made in papers
available on line here
and here.

The envelope of SN 1987a will strike its circumstellar ring in
12 +/- 3 yr. after explosion (A.D. 1999 +/-3), the exact time depending weakly
on the uncertain density of diffuse gas between the supernova and the
ring; Luo et al

We present
models for the hydrodynamics of the impact of the envelope of
SN 1987A with its inner circumstellar ring and for the resulting
X-ray spectra and light curves. If the impact begins in A.D.
2000...;
Borkowski et al

In
2000, the shock wave arrived at the circumstellar ring (5) (6) and was
reported in abstracts available on line here
and here.

We present observations of supernova remnant SN 1987A made with the Hubble
Space Telescope.... Space Telescope Imaging Spectrograph (STIS) spectra confirm
that this spot is the result of a ~300 km/sec shock entering the inner
circumstellar ring at the first point of contact by the supernova blast
wave; Michael

The full-scale interaction between the blast wave from SN 1987a and its
circumstellar equatorial ring (ER) has begun; Lawrence et al

So, we have not only the Panagia
et al findings, but
confirmation of his work in the predicted arrival of the shock wave from the
SN1987A event. These predictions have been made (and confirmed) independently
by several astronomers. SN1987A is 167,000 light years away and its light
has taken 167,000 years to reach us thus effectively refuting claims for a 10,000
year old Universe once and for all.

Would
a change in the speed of light affect these findings

There remains only one other creationist
objection to deal with; an alleged change in the speed of light since SN1987A went
supernova. This objection can be addressed by:

simple trigonometric considerations

spectrographic analysis of light
from the supernova itself.

Trigonometric
Considerations

Let
us imagine that the speed of light was considerably greater at the time of the
supernova than today. Creationists could use this supposition to suggest
that light has traversed the space between the supernova and Earth more
quickly than would be the case if the speed of light has been constant at the
speed observed today. The argument would then go that although the distance
to SN1987A is 167,000 light years, light could have traversed that distance
in less than 167,000 years.

However,
if the speed of light was greater at the time of the occurrence of the supernova
then the absolute distance to the circumstellar ring would be proportionately
more than we calculate based on the current speed of light. The angular
distance from the supernova to the circumstellar ring is not in question. By comparing
the absolute and angular distances, we would arrive at an absolute distance
to the supernova greater than that based on a constant speed of light. This would
yield a time for the light to traverse the space between the supernova and Earth
the same as or greater than the time derived from a constant speed of light
- ie the same as or greater than 167,000 years (since at some time the
speed of light would have had to decrease to what we observe today). So
a decaying speed of light offers no comfort to the creationist position.

But
from other considerations, we can be sure that the speed of light has not changed
significantly.

Spectrographic analysis of light
from the supernova itself

Any change in the speed of light will show
up as either a change in the decay rates of short half-life radioactive isotopes
or a change in the energy levels of those isotopes.

For example, if
light was twice as fast at the time SN1987A occurred as now, then an isotope
with a 60 day half life would seem, in spectrographic data, to have a 120 day
half life. This is because the light would travel the same distance in 60 days
at the time of origin, as it would cover in 120 days when it reaches Earth. Or,
the energy level of those isotopes would change according to E=mc˛. So, if the speed of
light (c) were twice as fast at the time of SN1987A as it is now, radioactive
isotopes would release four times as much energy on decay as they are observed
to do now..

Some of the papers
supporting a consistent radioactive decay rate and energy at the time and place
of SN1987A with modern, Earth bound values (7), (8), (9) are available
here,
here
and here

We present UBVRI photometry of the Type II supernova 1987A ....
the general shape of the bolometric light curve is close to the predicted curve
based on radioactive decay of 56Co in the remnant; Hamuy et al

We present ... photometry of SN 1987A in the Large Magellanic
Cloud .... The bolometric luminosity has declined with an e-folding time of
100.5 days, roughly consistent with the e-folding time of 111.3 days for the
radioactive decay of 56Co; Suntzeff et al

We derive the ultraviolet-optical infrared (uvoir) bolometric
luminosity evolution of SN 1987A .... this method is more accurate than
estimates of the uvoir bolometric luminosity based on the integration of
broad-band magnitudes. We show that between days 130-300 SN 1987A declined ...
with an e-folding time of 109.6 +/- 0.3 days, consistent with the thermalized
energy released by the radioactive decay of 56Co; Bouchet et al

Conclusion

We have now established
by trigonometric measurement that SN1987A is at a distance of about 167,000
light years and verified the speed of light is not significantly changed since
the time and place of SN1987A. This demonstrates that the events surrounding
Supernova 1987A took place some 167,000 years ago and YEC is therefore falsified.